Electrical bonding coupling



2 Sheets-Sheet 1 J. w. SANGER-STEVENS I ELECTRICAL BONDING COUPLING July 18, 1950 Filed May 1, I947 INVENTOR 5267mm Jzmesifjlk'am y 13, 1950 J. w. SANGER-STEVENS 2,515,899

ELECTRICAL BONDING COUPLING Filed May 1, 1947 I 2 Sheets-Sheet 2 B I J'/ ATTORNEY Patented July 18, 1950 f 'land,"assignor, by mesne assignments, to Radio Corporation of America, New York, N. Y., a corporation of Delaware Application May 1, 1947, Serial No. 745,296

In Great Britain March 27, 1946 This inventionrelates to electrical bonding couplings and more particularly to bonding couplings for use in so called"screening harnesses' .ffor internal'combustion engine ignition systems and the like for bonding the normally provided flexible screening tubes to the appropriate normally provided fixed "tube or tubes.

Asis' Well known, it is usual to provide the ignition systems'of f aircraft engines with an earthed screening harness whose purpose is to prevent radiation from the ignition system and consequent interference with nearby radio apparatus. Such a; screening harness usually comprises a fixed metal tube-ortubes connected by flexible metal'tubes (often braided) to the magof the harnessshall' be well bonded together without the risk of coming undoneunder the effects of vibration; and in our British Patent Specification No. 5111448 we describe a form of self-locking; readilydetachable and simple coupling means which is electricallyof high efficiency for bondingthepartsof engineignition harnesses together.

Experience has, however, shown that failure -canoccur (and upon occasion does occur) for a reason which has not hitherto been appreciated. Hitherto it has been assumed that the flexibility of theflexible tubes in a screening harness is sufiicient to take up for an irregularities of length, distance, and spacing in and between the different parts of a harnessbonded together by the couplings. However, inpractice this is not always so, for the compressibility of the tubes and other parts of the harness is limited and 2 Claims. (Cl. 285--162) manufacturing errors, accumulated tolerances,

locked) to positions in which-theparts of the harness are not adversely strained. In effect, as will be seen later, the invention in one embodiment provides a coupling which is generally like that described in our copending British Patent Specification No. 511,448, but which permits of telescopic adjustment and is capable of being made substantially airtight.

According to this-invention, one part of an internal combustion engine ignition screening harness or the like is bonded to another by a bonding couplingcomprising a tubular member which is carried by one part and is dimensioned and shaped to permit of telescopic movement with referenoe to the other, said member being split longitudinally so as to render it deformable radially, with means being provided for producing such radial deformation whereby said member may be firmly gripped in any desired position in its range of telescopic adjustment.

In one way of carrying out the invention, a bonding coupling between two parts of a harness comprises a first tubular member attached to one end'of one of the parts, a split sleeve slidably carried upon said member and having a tapered circular surface, a union nut also carried upon said member, and a split second tubular member threaded to receive the union nut and dimensioned to receive the end of the first member telescopically, and provided with a tapered circular surface to cooperate withthat on the sleeve.

In another way of carrying out the invention, a bonding coupling between two parts of a harness comprises a ferrule of tubular'form adapted to be attached to one part and to telescope over the other (or over a member carried thereby said ferrule having one or more portions providing a split tubular skirt and a groove retaining a rubber or like deformable ring, and a compression clip for radially deforming the split skirt so as to draw it down firmly on to said other part (or member) and compress the ring when a, desired position of telescopic adjustment has been achieved.

The invention is illustrated in the accompanying drawings, in which:

Fig. 1 is a sectional elevation of one embodiment;

Figs. 2, 3 and 4 are enlarged views of the parts I, l and 4, respectively, of Fig. 1;

Fig. 5 is a side view, partly in section, of another embodiment;

Figs. 6, 7 and 8 are views, respectively, of parts 8, 9 and H of Fig. 6Figs. 6 and 7 being enlarged; and

Fig. 9 is a sectional elevation of a further embodiment.

Referring to Fig. 1, a tubular member or ferrule I having a ring groove la (see Fig. 2) near one end is attached at its other end to one of the parts 2 to be coupled. Over this ferrule are slipped, in the order stated, a union nut 3, a split sleeve 4 split at M, which can slide on the ferrule l and have part of its outer surface tapered at 41) (see Fig. 4), and a sealing ring 5 which engages in the ring groove I a and secures the nut 3 and sleeve 4 against loss. To the other coupled part 6 of the harness is attached a second tubular member or nipple i (Fig. 3) which is threaded at the end remote from said part to receive the union nut, said end being split or slotted at la and also internally tapered at lb in correspondence with the taper on the sleeve.

To couple the parts, the ferrule l with its sleeve 4 and ring 5 is pushed into the nipple l and the nut 3 is screwed up firmly but not tightly. The joint is now made. but not locked and the ferrule can be telescoped with reference to the nipple until a desired position of adjustment is obtained; the sealing ring 5 (which is a piston fit in the nipple 1) making a substantially gastight joint. The nut 3 is then screwed up hard, forcing the split tapered sleeve 4 hard into the mouth of the split tapered end of the nipple I, thus radially distorting these two parts and locking the coupling.

In the embodiment shown in Fig. 5, one part of the harness (for example a flexible tube 2') is fitted into (for example screwed and soldered into) one end of a first circular ferrule 8 (Fig. 6). Over this is fitted and. suitably secured the larger diameter end of a second ferrule 9 (Fig. 7), which is of internally stepped formation (1. e., stepped at so.) so as to be of larger internal diameter over part of its length than over the remainder. In the internal step is a rubber or similar packing ring 10 and the two ferrules are so fitted together that this ring lies between the step and the end face of the first ferrule B. The smaller diameter length of the second ferrule 9 issplit longitudinally at 9b and has an internal diameter about the same as that of the first ferrule 8 and about the same as the external diameter of the other harness part B, which is shown as a solid tube. Over the split end of the second ferrule is slipped a compression clip such as a hose clip one form of which is shown separately in side view in Fig. 8.

To couple the parts the solid tube 6 is pushed telescopically through the second ferrule 9 into the first ferrule 8 and when a desired position of telescopic adjustment has been achieved the compression clip II is tightened down binding ill the split skirt 9b firmly on to the solid tube, thereby making a good mechanical and electrical connection which is also by reason of the rubber or like packing ring l0 substantially an air-tight joint.

The modification shown in Fig. 9 will be to a large extent self-explanatory from the figure in view of the description already given of Figs. 5 to 8 inclusive, for Fig. 9 shows a construction which is in main principle the same. In Fig. 9 the rubber or similar sealing ring I0 is positioned in a groove 8a formed externally on a solid ferrule 8' secured to one part of the harness 6'. Over the ferrule 8' is a second ferrule 9' which is secured to the other coupled part of the harness '2' (e. g. a flexible tube) and is stepped at 9a and provided with a split skirt at 912. A gastight telescopic joint is formed as before between the parts 8, 9' by means of the ring Ill and a hose clip or the like II is provided to lock the kirt 91) down on to the ferrule 8a after telescopic adjustment has been made.

What is claimed is:

1.. A coupling for bonding one part ofan internal combustion engine ignition screening harness or the like to another, comprising a first tubular member which is carried by one part and is dimensioned and shaped to provide for telescopic movement with reference to a second tubular member, said second member being split longitudinally so as to render it deformable radially, said first tubular member having an annular groove for retaining packing material, and means being provided for producing such radial deformation whereby it may be firmly grippedin any desired position in its range of telescopic adjustment.

2. A coupling as claimed in claim 1, characterized in this, that said first tubular member is attached to one end of one of the parts, a split sleeve slidably carried upon said first member and having a tapered circular surface, said means comprising a union nut also carried upon said first member, said second tubular member being externally threaded to receive the union nut, and dimensioned to receive the end of the first tubular member telescopically, and provided with a tapered circular surface to cooperate with that on the sleeve.

JAMES WILLIAM SANGER-STEVENS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 753,141 Kerr Feb. 23, 1904 1,292,060 Richards 1 Jan. 21, 1919 1,295,106 Bowlzer Feb. 25, 1919 

